ROLL STAND FOR FEEDING PAPER WEB FROM A ROLL

Abstract: Roll stand for feeding paperweb to i.e. a printing press comprising a rotating reel (1) for a first roll (8), from which a web is fed, and a second roll (11), which is to replace the first roll (8) when its diameter has decreased to a previously determined value, and also comprising means for splicing of the expiring web (9) to the replacement roll (11), and means for cutting said web (9). The roll stand (1) comprises two roll spindles (7.1, 7.2). Each spindle (7.1, 7.2) is connected to an acceleration motor (16) by a free-wheel drive transmission (10) in a first frame end section (2), preferably arranged in direct connection to each spindle (7.1, 7.2).

Description: ROLL STAND FOR FEEDING PAPER WEB FROM A ROLL TECHNICAL FIELD The present invention concerns a roll stand for feeding paper web from a roll to i.a. a printing press in which the paper web is furnished with a printing and cut into sheet. The roll stand according to the invention in¬ cludes a rotating reel for a first roll, from which a pa¬ per web is fed, and for a second roll, which is intended to replace the first roll e.g. when its diameter has de¬ creased to a previously determined value. BACKGROUND TECHNICS Roll stands of the kind mentioned in the pream¬ ble are known from i.a. the American patent publication US 4 194 701 (US Re. 31 192). The roll stand described in the publication mentioned includes a reel, which is tur- nable between two positions, a first expiring roll being in a first position when the second roll, intended to re¬ place the first roll, being in its second position. At the end of the expiring of the first roll, when its dia¬ meter is reduced to a previously determined value, the second roll is accelerated in that way that its periphery velocity will be the same as the velocity of the expiring paper web. This is brought about by means of a separate drive roll which is brought into contact with the enve¬ lope surface of the second roll. A press roll after that is brought into contact with the paper web, pressing the same to the envelope surface of the second roll, the envelope surface of this adhering to the underside of the paper web making the paper web also to expire from the second roll. The paper web from the first roll after that is cut by a knife arranged on the roll stand separated from the reel. The known roll stand shows mainly two drawbacks. The first drawback is that the acceleration device is acting on the envelope surface of the second roll, which can make the paper web to break if it is manufactured of a quality with a low strenght and the second roll is ac¬ celerated too fast. Another drawback is that the knife for cutting the paper web from the first roll is arranged on the roll stand, making difficulties and use of paper rolls with different diameters. DESCRIPTION OF THE INVENTION The purpose with the present invention is to bring about a roll stand for feeding of paper web to i.a. a printing press not showing the drawbacks as at the up to now known roll stands. The roll stand according to the invention includes a rotating reel for a first paper roll, from which a paper web is fed, and a second paper roll, intended to replace the first roll e.g. as its diameter has decreased to a previously determined value. The roll stand according to the invention also includes means for splicing the expiring paper web to the paper web in the second roll and means for cutting the paper web from the first roll. The roll stand according to the invention is characterized in that an angle gauge is mounted on the reel for measurement of a turning of the same, an indicator is arranged for indicating a position to which the second roll is turned at computing of the diameter of the second roll, the angle gauge beeing con¬ nected to a device for computing of said diameter and adjusting the speed of rotation of the second roll at the splicing of the paper webs. Each roll spindle in the reel is connected to an acceleration motor by a drive transmission arranged in a first gable. Preferably each roll spindle is connected also to a brake device by a brake transmission arranged in a second gable. In order to admit driving of the first one or the other one of the roll spindles these are con¬ nected to the acceleration motor by a free-wheel, prefe¬ rably arranged in connection with each roll spindle. More characterizing features and details regar¬ ding the roll stand according to the invention will be clear from the description according to the drawings below and from the claims. DESCRIPTION TO DRAWINGS The invention is described below as an embodi¬ ment in connection with the enclosed drawings. Figure 1 shows a roll stand with a reel for two rolls according to the invention observed from one side and in a direction coinciding with the directions of the roll spindles of both of the rolls. Figure 2 shows the roll stand according to fi- gure 1 in a direction normal to the directions of the roll spindles of the rolls. Figure 3 shows the roll stand according to fi¬ gure 1 observed from the other side. Figure 4 shows the roll stand according to fi- gure 2 enlarged and including a drive device and a breaking device. Figure 4 A-C shows details of the roll stand. Figure 5 shows schematically a part of a reel observed from one side in a direction coinciding with a direction of the roll spindles of both rolls. Figure 6 and 7 shows details of a knife built in in the reel. Figure 8 shows one side of the reel according to figure 4 observed in an opposite direction and including the drive device. Figure 9 shows a first gable of the reel obser¬ ved from the left in figure 8. Figure 10 shows schematically a drive transmis¬ sion for the roll spindels in the first gable. Figure 11 shows the other side of the reel ac¬ cording to figure 4 observed in an opposite direction and including the brake device. Figure 12 shows schematically a brake transmis¬ sion for the roll spindles. Figure 13 shows a second gable on the reel ob¬ served from the right in figure 11. Figure 14 shows the brake device according to figure 10 enlarged. Figure 15 and 16 show the arrangement of an angle gauge connected to the reel. The roll stand according to the invention, shown in figure 1-3, includes a reel 1, showing a first gable 2 and a second gable 3 connected by two knife bars 4. Each bar is surrounded, as shown in figure 4 and 5, by a sup¬ porting roll 5 radially projecting at each side of the bar and including a radially movable knife 6 extending in the longitudinal direction of the knife bar 4. A first roll 8 is arranged on a first roll spindle 7.1, from which a paper web 9 is fed off as shown in figure 5. On a second roll spindle 7.2 a second roll 11 is arranged, intended to replace the first roll 8 as the diameter of this roll has decreased to a previously determined value. The first gable 2 is, as shown in figure 5 and 8, connected to a drive motor 13 by a drive shaft 14 ar¬ ranged in bearings in the stand and a first motor gear 15, by which the reel 1 can be turned around a centre axis. The first gable 2 includes a drive transmission 10, shown in figure 10, which is connected to an acceleration motor 16 by an acceleration shaft 17 and a second motor gear 18 arranged between the shaft and the motors. The drive transmission 10 includes a first spindle gear wheel 19.1 provided with a free-wheel and connected to the first roll spindle 7.1 and a second spindle gear wheel 19.2 provided with a free-wheel connected to the second roll spindle 7.2. The acceleration shaft 17 carries a first centre gear wheel 20 connected to the two spindle gear wheels 19.1, 19-2 by an intermediate gear wheel 21. By the drive motor 13 the reel 1 can be turned stepwise, i.e. in steps of 180° each time a new roll 11 shall be brought into the reel 1. The function of the acceleration motor 16 is closer described below. The second gable 3 includes a b ^ake transmis¬ sion 12 corresponding the drive transmission 10 in the first gable 2, by which the first roll spindle 7.1 by a first socket-shaped brake shaft 22 is connected to a first brake device 23. The second roll spindle 7.2 is by a second brake shaft 24 connected to a second brake device 25 as shown in details in figure 14. The brake transmission 12 includes a first brake gear wheel 26.1 connected to the first roll spindle 7.1 and a second brake gear wheel 26.2 connected to the second roll spin¬ dle 7.2. The first brake shaft 22 carries a second centre gear wheel 27 connected to the first brake gear wheel 26.1 by two intermediat gear wheels 27. The second brake shaft 24 carries a third centre gear wheel 28 connected to the second brake gear wheel 26.2 by three intermediate gear wheels 27. The reel 1 further is mounted in bearings in a housing 29 by its second gable 3, surrounding the brake devices 23, 25 and connected to the stand of the device by another socket-shaped reel shaft 30. By the brake transmission 12 both of the brakes 23, 25 are caused to rotate in opposite directions. The brake device 23, 25 are electro-mechanically operated from a central operation unit. An angle gauge 31 for the measurement of absolu¬ te angles of the turning of the reel 1 at splicing of the paper web 9 is connected to the drive shaft 14 of the reel 1 as shown in figure 4 and 8. The angle gauge 31 also is shown in detail in figure 15 and 16. The knife bars 4 as shown in figure 4 A, B and in figure 6 and 7 in a cross section include a radially movable knife 6 in the shape of a knife olade 6.1 along each knife bar 4 and mounted on a spring plate 6.2 along the knife bar 4. In a retracted position the knife blade 6.1 is protected inside a protecting plate 6.3 also ex¬ tending along the knife bar 4. The protecing plate 6.3 projects a distance a = 3 mm from the outer side of the knife bar 4. At cutting of a paper web 9 the knife blade 6.1 is brought to project beyond the projecting plate 6.3 by means of electrical adjusting means 6.4 activated from the central operation unit. At the end of a feeding from the first roll 8, as shown in figure 5, the first roll 8 is placed in a position (A) as shown by turning of the reel 1 as its diameter has decreased to a first previously determined value. The paper web 9 from the first roll 8 runs over the supporting rolls 5 at the uppermost knife bar 4 and to e.g. a printing press, not shown in the figures, where the paper web is printed and cut into sheet. The second roll 11 after that has been placed in the position (B) as shown and been provided whith glue along portions of its periphery surface in a known manner. The diameter of the second roll 11 is measured by turning the reel 1 clock¬ wise in that way that the envelope surface of the second roll 11 is brought into contact with an indicator 32, e.g. a photocell, measuring the turning angle of the reel 1 by the angle gauge 31 making a measurement which is computed into a diameter of the second roll 11. The indi¬ cator 32 preferably is located at the side of the reel 1 and the expiring paper web 9, the running velocity of which is continuously indicated by a measuring device 34 as shown in figure 5. As the diameter of the first paper roll 8 has decreased to a second previously determined value the second roll 11 is accelerated until its peri¬ phery velocity is the same as the velocity of the expi- ring paper web 9. A press roll 33 at that occasion is caused to move to the paper web 9 in that way that the periphery surface of the second roll 11 is brought into contact to the underside of the expiring paper web 9. The periphery surface of the second roll 11 is caused to stick to the underside of the paper web 9, the web begin¬ ning to expire from the second roll 11. On the same time the first brake device 23 of the first roll spindel 7.1 is activated avoiding eventual slack between the first roll 8 and the press roll 25. The knife 6 in the upper- most situated knife bar 4 after that is activated and caused to cut off the paper web 9 from the first roll 8, the rotation of which after that is braked completely by means of the first brake device 23. Feeding off from the second roll 11 after that is carried out until its dia¬ meter has decreased to the first previously determined value, the reel 1 again is caused to turn 180 in that way that the second roll 11 is moved from the original position (A) to the new position (B). The drive transmission 10 in the first gable 2 is connected to the acceleration motor 16 by the accele¬ ration shaft 17. As the acceleration motor 16 causes the acceleration shaft 17 to rotate clock-wise (I) as shown in figure 10, the first spindle gear wheel 19.1 on the first roll spindle 7.1 is caused to rotate by a locking of the free-wheel on the first spindle gear wheel 19-1- On the same time the spindle gear wheel 19.2 on the se- cond roll spindle 7.2 is brought to rotate by its free¬ wheel without causing the second roll spindle 7.2 to ro¬ tate. As the acceleration motor 16 makes the acceleration shaft 17 to rotate clockwise (II) in the same way the se¬ cond roll spindle 7.2 is caused to rotate anti-clockwise by a locking of the free-wheel of the spindle gear wheel 19.2 on the second roll spindle 7.2 while the first roll spindle 7.1 is not affected. By arranging one respecti¬ vely two intermediate gear wheels 21 between the first centre gear wheel 20 on the acceleration shaft 17 and each spindle gear wheel 19.1, 19.2 is achieved that each roll spindle 7.1, 7.2 becomes the same direction of rota¬ tion irrespective of the acceleration shaft 17 rotates anti-clockwise or clockwise. Thus each of the roll spind¬ les 7.1, 7.2 can be connected for driving only by choo- sing direction of rotation of the acceleration motor 16. The spindle gear wheels 19.1, 19.2 on each roll spindle 7.1, 7.2 are provided with free-wheel hubs as mentioned, by which a positive driving of each roll spindle 7.1, 7.1 only is done as long as the envelope velocity of the second roll 11 is lower than the running velocity of the expiring paper web 9. As the paper web starts to feed off from the second roll 11 in that way that the rate of rotation of the same is bigger than the rate of rotation achieved by the acceleration motor 16, the free-wheel hub of said roll spindle 10 starts rolling freely and the acceleration motor 16 is stopped. The roll 11 continues to rotate freely by the free-wheel hub. The drive motor 13 for turning the reel 1 in steps as well as the acceleration motor 16 preferably are consti¬ tuted by electrical alternating-current motors which are controlled by a common frequency control. In an embodi- ment of the invention where continuous-current motors are used also these motors are controlled by a corresponding common control of the electrical feeding.

Claims: CLAIMS 1. Roll stand for feeding paper web to i.a. a printing press comprising a turnable reel (1) for a first roll (8), from which a web is fed, and the second roll (11), which is to replace the first roll (8) when its diameter has decreased to a previously determined value, and also comprising means for splicing of the expiring web (9) to the web in the second roll (11) and means for cutting the web (9) from the first roll (8), the reel (1) comprising two roll spindles (7.1, 7.2) each of them con¬ nected to an acceleration motor (16), c h a r a c t e ¬ r i z e d in that the acceleration motor (16) is connec¬ ted to a drive transmission (10) by an acceleration shaft (17) carrying a first centre gear wheel (20), said first centre gear wheel (20) connected to a first spindle gear wheel (19.1) of a first roll spindle (7.1) by an odd num¬ ber of intermediate gear wheels (21 ) and connected to a second spindle gear wheel (19.2) of a second roll spindle (7.2) by an even number of intermediat gear wheels (21), and in that free-wheels are arranged in connection to each roll spindle (7.1, 7.2). 2. Roll stand according to claim 1, c h a ¬ r a c t e r i z e d in that the spindle gear wheels (19.1, 19.2) include free-wheel hubs. 3- Roll stand according to claim 1 or 2, c h a r a c t e r i z e d in that a drive motor (13) is arranged to turn the reel (1 ) and that the drive motor (13) and/or the acceleration motor (16) are electrically fed by an electric control means, preferably a frequency control means if these motors are constituted by alterna¬ ting-current motors. 4. Roll stand according to any of the claims 1-3, c h a r a c t e r i z e d in that an angle gauge (31) is connected to the reel (1) for measurement of a turning movement of the reel (1), an indicator (32) being arranged for indication of a position into which the se¬ cond roll (11) is turned, the angle gauge (31) being connected to a device for computing of the diameter of the second roll (11) and adjustment of the rotation velo¬ city of the second roll (11) at splicing of the paper webs. 5. Roll stand according to any of the claims 2-4, c h a r a c t e r i z e d in that each roll spindle (7.1, 7.2) in the reel (1) is connected to a brake device (23, 25) by a brake transmission (12). 6. Roll stand according to claim 5, c h a - r a c t e r i z e d in that a first roll spindle (7.1) is connected to a first brake device (23) and a second roll spindle (7.2) is connected to a second brake device (25). 7. Roll stand according to claim 6, c h a - r a c t e r i z e d in that the first brake device (23) is connected to a brake transmission (12) by a first brake shaft (22) which carries a second centre gear wheel (27), the second brake device (25) being connected to the brake transmission (12) by a third centre gear wheel (28), the second centre gear wheel (27) being connected to a first brake gear wheel (26.1) of the first roll spindle (7.1) by an even number of intermediate gear wheels (27) and the third centre gear wheel (28) being connected to a second break gear wheel (26.2) of the se- cond roll spindle (7.2) by an odd number of intermediate gear wheels (27). 8. Roll stand accordning to any of the claims 1-7, c h a r a c t e r i z e d in that the means for cutting the paper web comprise at least one knife (6), being arranged in the reel (1). 9- Roll stand according to claim 8, c h a ¬ r a c t e r i z e d in that the reel (1) comprises a first gable (2) and a second gable (3) between which two knife bars (4), each including a knife (6), and two roll spindles (7.1, 7.2) for carrying the first roll (8) re¬ spectively the second roll (11), are diametrically arranged. 10. Roll stand according to claim 9, c h a ¬ r a c t e r i z e d in that the knife bars (4) and the roll spindles (7.1, 7.2) are arranged in pairs in two normal planes.

Inventors: ANDREASSON BENGT, ANDREASSON, BENGT
Applicants: ANDREASSON BENGT, ANDREASSON, BENGT
Application year: 1994
Main classification: B65H19
IPC codes: B65H19, B65H23